Trench digging machine



June 5, 1956 G. W. M ININCH TRENCH DIGGING MACHINE 2 Sheets-Sheet 1Filed March 28, 1952 MVSAJTOOM Glenn YYLcInLncJg W, WM 715% (ATTcmE-Y/June 5, 1956 G. w. MCININCH TRENCH DIGGING MACHINE 2 Sheets-Sheet 2Filed March 28, 1952 narzmw'ova v Glem 1 am qz/ ia fi CATTORIUBYM UnitedStates Patent 2,748,504 TRENCH mourns MACHINE Glenn Mclninch, Omaha,Nebn, assignor to Auburn Machine Works, Inc., Auburn, Nebn, acorporation of Nebraska Application March 28, 1952, Serial No. 279,015 2Claims. (Cl. 37-86) This invention pertains to trench diggers, and moreparticularly to an improved dirt baffling arrangement therefor.

While the invention is applicable to trenchers generally, it findsparticular application to trenchers of the general type disclosed andclaimed in U. S. Patents Nos. 2,519,075, 2,519,076, and 2,519,077, toFriedrich J. Schmidt, assigned to the assignee of this application.

One principal object of the invention is to provide a trencher having anefiective bafiiing arrangement for intercepting and scattering thestream of earth elevated by the trencher.

Another object is to provide a chain type trencher having an improvedarrangement for propelling the elevated dirt stream forwardly of thechain.

As applied to a trencher of the type having a swinging beam equippedwith a digger chain for elevating a stream of earth, it is a furtherobject to provide a bafiling arrangement for diverting the earth streamdownwardly and outwardly without interfering with the swinging movementof the beam.

Further objects and advantages will be apparent from the followingdescription, taken with the accompanying drawing in which:

Figure 1 is a general perspective view of a tractormounted trenchdigging machine constructed in accordance with the invention.

Fig. 2 is a side elevational section taken centrally through themachine.

Fig. 3 is an enlarged fragmentary rear perspective view showing a dirtbafiling arrangement incorporated in a digger beam and a mounting frameon the machine.

Fig. 4 is a rear perspective view of the mounting frame with the diggerbeam removed for clarity of illustration.

Fig. 5 is a front perspective view of the mounting frame, shown detachedfrom the tractor.

While the invention is susceptible of various modifications andalternative constructions, there is shown in the drawings and willherein be described in detail the preferred embodiment, but it is to beunderstood that it is not thereby intended to limit the invention to theform disclosed, but it is intended to cover all modifications andalternative constructions falling within the spirit and scope of theinvention as expressed in the appended claims. 7 Referring to thedrawings with greater particularity, the invention is illustratedtherein as embodied in a trench digger 10 adapted for mounting on avehicle such as a farm tractor 12 shown generally in Figs. 1 and 2. Amounting frame 14 is detachably secured to the tractor to provide asupport for a digger beam 16. The beam is pivotally mounted for swingingmovement in a vertical plane by means of a pair of hollow shafts orsleeves 18 (Fig. 3) journaled in suitable bearings 20 (Fig. 4) on themounting frame 14. The inner ends of the sleeves 18 are connected to acentral yoke or bracket 22 which in turn is secured to the upper end ofthe beam 16. A suitable mechanism is provided for rotating the shaftsice 18 and thus lowering the beam into a rearwardly and downwardlyinclined operative position, as shown in Figs. 1 and 2. Reference ismade to the above-mentioned Schmidt patents for a detailed descriptionof such a mechanism. For the present purposes, it will suflice to notethat a sprocket wheel 24 is mounted on one of the hollow shafts 18, andthat a suitable drive, not shown, powered by hand or by the tractor isprovided to rotate the sprocket wheel 24.

The beam is provided with a digging mechanism comprising an endless loopof digger chain 26 trained around a pair of sprocket wheels 28 and 30 atthe upper and lower ends of the beam, the sprocket wheel 28 at the upperend of the beam being positioned between the arms of the yoke 22 andmounted on a shaft 31 telescopically received in the hollow shafts 18. Aplurality of digger blades 32 are spaced along the chain. Mounted on theshaft 31 is a sprocket wheel 33 which is driven by a suitable mechanism(not shown) in a direction such that the digger blades on the lowerflight of the chain move upwardly so as to elevate a stream of earth.The digger blades and the mechanism for driving the chain may beconstructed as disclosed and claimed in the above-mentioned Schmidtpatents, to which reference is made for a detailed description. For thepresent purpose it will suffice to note that the blades are smoothlycontoured and unbroken by pockets or the like so that the earth isscraped or impelled upwardly by impact, and is discharged in front ofthe chain rather than being carried over the upper sprocket and dumped,as in the case of the more conventional bucket-type elevators.

The tractor is advanced at a slow rate, coordinated with the speed ofthe digger chain 26, by means of a suitable mechanism (not shown), whichmay be of the type disclosed and claimed in the aforesaid Schmidtpatents. The driving wheels or a winch 34 on the tractor may be utilizedselectively or in combination to provide tractive effort.

In accordance with the invention, provision is made for separating theupwardly moving stream of earth from the digger blades and propellingthe earth stream away from the digger chain. This is accomplished in thepresent case by mounting a guiding element in the form of an idlersprocket 40 on the beam 16 to engage the lower flight of the conveyorchain 26 so as to introduce an upward turn therein. The sprocket isspaced below the beam 16 at a point intermediate the main sprockets 28and 30 so as to deflect the chain outwardly of the beam. When the beamis in its operative position as shown in Figs. 1 and 2, the idlersprocket 40 is positioned between the upper sprocket 28 and the groundlevel. Thus the chain negotiates the upper turn around the sprocketshortly after emerging from the ground, and in consequence, the streamof earth is impelled tangentially of the chain by centrifugal force.Much the greater part of the stream of earth is thereby disengaged fromthe chain so that a minimum amount of earth is carried upwardly towardthe upper sprocket 28.

In the present instance the idler sprocket 40 is advantageously utilizedto drive one of a pair of augers 42 and 44 which distribute the elevatedearth laterally of the trench formed by the digger blades. The otherauger 44 is driven by a second idler sprocket 46 engaging the upperflight of the digger chain 26. In the presentinstance the forward auger42 is elevated above the ground level so as to perform an initialleveling operation, while the rearward auger 44 is substantially attheground level so as to complete the earth removing operation. The angers42 and 44 may be constructed and arranged as disclosed and claimed inthe above-mentioned Schmidt patents.

As another feature of the invention, provision is made 3 forintercepting and forcibly scattering the earth stream thrown upwardly bythe digger chain 26. In furtherance of this aspect of the invention, abaffle in the form of a downwardly flanged horizontalplate50 (Figs. 2and is positioned tangentially. of theidlerqsprocketAO substantiallyabove and somewhat forwardly thereof. The rearward edge of the plate50is disposed immediately in front of the'upward run ofthe conveyor chain26 so that the plate is effective to divert and scatter substantiallyall of the earth discharged by the digger blades upon their emergencefrom the ground. By scattering the earth over a considerable area, thebathe-50 facilitates the disposal operation performed by=the angers 42and 44.

The mounting frame 14 isv provided with a pair of generally rectangularside housings 52 and 54' (Figs. 4 and 5) between which the horizontalbaffle 50 extends. The housings project rearwardlyfrom a box-likeskeleton 56 (Fig. 5) adapted to ne'stover-the differential housing onthe tractor and to beattached'to the rear axle housings by means ofsuitable clamps 57.

Extending upwardly from the rear'edge of the horizontal baifle 50 is abaffle plate 58 running generally parallel to the path of the chain andinclined forwardly at a small angle to the vertical. A portion of thesmall quantity of earth carried upwardly by the chain from-the idlersprocket 40 is deflected rearwardly by the generally vertical baffie 58.The side housings 52 and 54 terminate at their rearward ends ingenerally semi-cylindrical detachable sprocket covers 60 and 61.

Fitting closely between the side housings 52 and 54 and in closeproximity to the vertical baflle 58 is an-arcuate generally drum-shapedshield 64 mounted radially on'the beam-supporting pivot shafts 18 forswinging movement with the beam. In this instance the-shield 64isattached to the shafts 18 by means of a pair of split collar clamps66. In cooperation with the horizontal bafile 50, ;the generallyvertical baffie 58, and the side housings 52 and 54, the arcuate shield64-interceptsthe earth thrown off by the cutter blades and incidentallyprotects the tractor operator and the mechanisms of the trencher and thetractor from flying earth.

While the operation of the trench Jdigging machine will be apparent fromthe foregoing description, it will be briefly summarized as follows:

After the tractor 12 has been maneuvered'into the desired position, thebeam 16 is loweredto bring the lower flight of the conveyor chain 26into contact with the ground surface and to swing the arcuateshield-upwardly into cooperative bafiiing relationship with the-plates50 and 58. Power is then supplied to thedigger chain 26 whereupon thedigger bladescut into the ground and the beam swings downwardly into-theearthso as to assume its normal inclinedposition, as shown in Figs. 1and 2. At the same time, thearcuate shield'swings upwardly into itspositionshownin these figures. The tractor is then set into-forwardmotion at a slow rate so that the digger blades on the lower flight ofthe cutter chain 26 cut into the inclined working face of the trench.The earth loosened by the blades is carried upwardly in a continuousstream. As the-cutterchain emerges from the ground and negotiates theturn around thesprocket 40, the greater part ofthe stream oflearthis-disengaged from the blades by centrifugal force andimpelledtangentially of thesprocket; against-the underside of thehorizontal baffle 50. Because of the elevated position of the baflie,the stream, of earth is scattered laterally and forwardly overafcorisiderablelarea. The forceful impingement of,,the earth uponthe-:batfle shatters the larger lumps so that the earth movingoperation: performed by the augersAZandAA is ;c 1onsiderablyfacilitated.

The relatively small amount of earth carried upwardly by the chain 26from the sprocket 40 is diverted rearwardly and downwardly by thevertical baflie 58 and the arcuate shield 64 acting in cooperation withthe side housings 52 and 54.

When the trench digging operation has been completed, the beam 16 may beswung upwardly into an upright position for transportation to anotherlocation. As the beam 16 is swung upwardly, the arcuate shield 64 isrotated downwardly into an out-of-the-way-position. By virtue of itsinclined position forwardly of the conveyor chain, the generallyvertical baflle 58 offers no interference to the swinging movement'ofthebeam.

I claim as my invention:

1. In a trencher for mounting on-the rear end of a tractor or the like,the combination comprising a mounting frame, a beam pivoted at its upperend on the frame for swinging movement iu a vertical plane into an; operative position with the beam extending rearwardlyand downwardly intothe earth, an endless loop of cutter chain running around the beam in avertical plane and trained about the ends thereof, means for drivingthechain in a direction to effect upward -movement ofthe front flightthereof, a generally horizontal baflle on said frame, said horizontalbaflle having its rear edge closely adjacent the front flight of thechain near the upper .end of said beam for intercepting and scattering aportion of the earth propelled upwardly by thechain, an arcuategenerally drum-shaped shield mounted on-thebeam and enclosing the chainat the upper end of the beam and adjacent said horizontal bafllefor-intercepting earth carried to the rear of said horizontal baflle bysaid chain, and an additional baffle on said frame extending-upwardlyfrom the rear edge of said horizontal baffle adjacent said chain andimmediately forward of saidarcuate shield for intercepting earth passingbetween said horizontal bafile and said shield.

2. In a trencher for mounting on the rear end of a tractor or the like,the combination comprising a mounting frame, an elongated beam, pivotmeans supporting said beam adjacent its upper end onsaidframe forswinging movement about a horizontal axis transverse to the axis of thebeam to and from an operative position in which the beam extendsrearwardlyand downwardly into the earth, an endless loop of cutterchain-running around the beam in a vertical plane and trained-'abouttheends'thereof, means for driving said chain-in a direction 7 to effectupward movement of the front flight of the loop,

an arcuate shield dimensioned to extend crosswiseover the upper end ofthe beam, means supporting said shield in overlying relation to thechain at the upper end-of-the beam and to swing with the beam about theaxis Qfisaid pivot means, and means on said frame defining ahorizontallydisposed baffle having its rear edge positioned closelyadjacent the front edge portion :of said shield when the beam is in anoperative position so astointercept the earth propelled upwardly by thefront flightof said chain.

References Cited in the file of this patent UNITED STATES PATENTS1,239,474 French Sept. 11, fl 9-17 1,428,055 Paul Sept. 5-, 19221,767,017 'Scheckler June 24, 1930 2,231,983 Zuckerman Feb. 18,19412,519,077 Schmidt Aug. 15; 1950 2,551,883 Hunkler May 8,1951 FOREIGNPATENTS 7 608,794 'Great Britain -.Sept.'21-,:1-9.48

